The voice conversation is the most fundamental service of the mobile communication network and it is also the most important service, and also concerned by most users and operators. Its confidentiality and security are also one of important contents of the mobile network technology. At present, the mobile phone with the encryption conversation function receives more and more attentions, and especially the organizations and individuals, such as the sensitive department of the government, and the intelligence agency and so on, pay much attention to the security and confidentiality.
The conference telephone function of the mobile phone, based on its advantage of simple building and good mobility, is more and more widely used by people. The conference telephone is used mainly for three or more users to perform the conversation at the same time. For the initiator, the three-party conversation services have to be registered in the network side at first, and then it can be used.
The inventor of the application of the present invention finds that: the mobile phones with the encryption conversation function are basically based on the voice encryption and decryption from end to end at present, which does not need the network to participate, so it cannot perform the operation of encryption and decryption by using the security key encryption factor (Ki) in the network or the other keys generated by the Ki, such as the cipher key (abbreviated as CK) and so on.
In sum, the security of the current conference telephone service of the mobile phone is not high, and it is probably affected by other unknown non-encryption conversation.